1. Field of the Invention
The present invention relates to the field of image data processing, and more particularly without limitation, to the field of processing and visualizing of four dimensional data, such as time variant three dimensional image data.
2. Prior Art
Dynamic imaging of volume data is used in medicine to detect abnormalities in tissue perfusion, for example in the brain to diagnose an acute stroke or in the female breast for tumour detection and classification (cf. E. L. Barbier, L. Lamalle, M. Decorps (2001). “Methodology of Brain Perfusion Imaging”, Journal of Magnetic Resonance Imaging 13: 496-520; H. Degani, V. Gusis, D. Weinstein, S. Fields, S. Strano (1997). “Mapping pathophysiological features of breast tumors by MRI at high spatial resolution”, nature medicine 3:7, pp. 780-782; “Improved diagnostic accuracy in dynamic contrast enhanced MRI of the breast combined quantative and qualitative analysis” P-F Liu MD, J F Debatin MD, R F Caduff MD, G Kacl MD, E Garzoli MD and G P Krestin MD.)
The significance of dynamic information for diagnosis of tumours has been shown in the prior art. It is as such known that both morphological information based on high spatial resolution images in combination with dynamic temporal information of contrast agents intensity curves to measure tissue kinetics enhances tumour characterisation (cf. C. K. Kuhl, H. H. Schild (2000). “Dynamic Image Interpretation of MRI of the breast”, Journal of Magnetic Resonance Imaging 12, pp. 965-974.)
WO97/26507 shows an image processing apparatus for contrast enhanced MRI data in order to facilitate specific diagnosis of cancer. The wash-out slope after injection of a contrast agent is encoded in three different colors red, green and blue. One of the drawbacks of this method is that a lot of the information content of the time variant image data is lost due to this color-encoding scheme. Another major drawback is that this method can only be employed for coloring of time variant two dimensional image data but not for coloring and displaying time variant three dimensional image data. It is therefore an object of the present invention to provide for an improved coloring method and image data processing system as well as a corresponding computer program product.